EP1685772A1 - Composite sole for bicycle shoe provided with integrated anchor insert and bicycle shoe equipped with such sole - Google Patents

Abstract

The anchor (16) is encrusted in the core by a pressing operation; is integrated into the core by moulding; and is formed a housing infront of the core face. The core is carried out in a dense material. The anchor and the core are superimposed and separated by a transition course. An independent claim is also included for a sole shoe of bicycle.

Description

The invention relates to the field of bicycle shoes, and more particularly to the soles of these bicycle shoes.

It has long been known to develop bike shoes with a rigid sole to improve the ability of the shoe to transmit the full efforts of the cyclist to the bike training mechanism, starting with the pedals.

To do this, it is known to make soles of rigid plastic material, these materials being generally injected plastics reinforced by short fibers, for example short glass fibers. It is also known that the production of composite laminate soles (comprising at least one layer of resin-impregnated fibers) makes it possible to obtain even more rigid soles, but especially much lighter soles. Finally he known, for example documents US-5.406.723 and EP-1.442.670, to produce soles bicycle shoes composite laminates with a sandwich structure. In such a design, the sole comprises at least one core which is generally made of cellular material and which is interposed between lower and upper layers of composite material.

Furthermore, it is also known that a bike shoe is provided on the underside of its sole, a connecting block for cooperating with complementary connecting members, arranged on the pedal, to provide a disconnectable connection between the shoe and the pedal. As there are different connecting systems operating with spacers of different geometry, it is expected that these wedges are removably anchored on the sole, for example by means of screws. For this, there is provided an anchoring insert, which is for example provided with tapped holes to allow screwing anchor screws. However, in the documents cited above, the anchoring inserts are intended to be received in recesses in the upper face of the rigid sole. The inserts are then received between the upper face of the composite outsole and a mounting flange of the rod.

With this arrangement, the upper face of the composite outsole is complex to achieve, and the geometry of the obvious may be detrimental to the stiffness of the sole, requiring heavy and / or bulky corrective means, such as thicknesses of materials. additional, reinforcement grooves / ribs, etc.

The object of the invention is to propose a shoe sole which is particularly simple to manufacture and which has all the guarantees of rigidity and solidity required for optimum weight.

For this purpose, the invention provides a sole for a bicycle shoe, of the type in which the sole comprises at least one upper layer and a lower layer of composite material comprising at least one fiber web impregnated with a resin,
characterized in that the sole comprises, interposed between the composite upper layer and the composite lower layer, at least one anchoring insert which is provided to allow the attachment, under the sole, of a connecting member of the sole to a bike pedal.

• la figure 1 est une vue schématique en perspective et en vue de dessus d'une semelle rigide de chaussure de vélo selon l'invention ;
• la figure 2 est une vue schématique en perspective et en vue de dessous de la semelle de la figure 1 ;
• la figure 3 est une vue en coupe selon la ligne III-III de la figure 1 ;
• la figure 4 est une vue schématique en perspective illustrant un mode de réalisation de l'incrustation de l'insert dans un noyau pour la réalisation d'une semelle rigide selon l'invention ;
• la figure 5 est une vue agrandie d'un détail de la figure 3 ;
• la figure 6 est une vue similaire à celle de la figure 5 où est illustrée une première variante de réalisation de l'invention dans laquelle le noyau est surmoulé autour de l'insert ;
• la figure 7 est une vue similaire à celle de la figure 6 où est illustrée une deuxième variante de réalisation de l'invention dans laquelle l'insert et le noyau sont séparés par une couche de séparation.

Other characteristics and advantages of the invention will appear on reading the following detailed description, as well as on the following drawings:

• Figure 1 is a schematic perspective view and a top view of a rigid sole of bicycle shoe according to the invention;
• Figure 2 is a schematic perspective view and bottom view of the sole of Figure 1;
• Figure 3 is a sectional view along the line III-III of Figure 1;
• Figure 4 is a schematic perspective view illustrating an embodiment of the incrustation of the insert in a core for the realization of a rigid sole according to the invention;
• Figure 5 is an enlarged view of a detail of Figure 3;
• Figure 6 is a view similar to that of Figure 5 which is illustrated a first embodiment of the invention wherein the core is overmolded around the insert;
• Figure 7 is a view similar to that of Figure 6 which illustrates a second embodiment of the invention wherein the insert and the core are separated by a separating layer.

There is illustrated in the figures a rigid soleplate 10 intended to form at least a portion of the semellage for a bicycle shoe. The rigid sole 10 has an upper face 11 on which it is expected to bring a shoe upper (not shown), which can be built and reported on the sole according to any known technique. Said rod may for example be sewn, stapled and / or glued on a first mounting, which will for example be glued to the upper face of the sole 10.

The sole 10 is intended to give the shoe the desired rigidity, and is therefore constructed using laminated composite materials, that is to say materials in which one or more layers of fibers (glass fibers, carbon, aramid, etc ..., woven or simply agglomerated nonwoven web, using several types of fibers or not, etc ...) are impregnated with a rigid resin (polyurethane type, polyester, epoxy, etc. ..., thermoplastic or thermosetting). The resin then forms the matrix of the composite material, the fibers forming the reinforcements. The number of layers of superimposed fibers and their nature may vary depending on the level of rigidity, weight, strength and cost that are targeted. Likewise, all the processes for implementing composite materials are conceivable.

The rigid sole 10 has a lower face 12 which, depending on the case, may be apparent or not (possibly partially apparent) from the outside of the shoe. Indeed, in the case of a road bike shoe intended for practice in competition, for which the criterion of a minimum weight is essential, it can be provided that the shoe is provided with only small contact pads with the ground, these pads to prevent slippage and limit wear of the sole when the user walks with his shoes. However, these skates minimum size do not allow walking very easy. Also, for other models of shoes, it can be provided that the underside 12 of the rigid sole 10 is covered, partially or completely with another sole element (for example a natural or synthetic rubber outsole) . In the illustrated example, it can be seen that the lower face 12 has a central boss 14, while the upper face 11 is substantially smooth, while being curved so as to be conformed to the geometry of the plantar surface of the foot of the foot. 'user. Such a smooth upper face 11 is interesting from the point of view of comfort, since the user is not likely to be hindered by reliefs or discontinuities of unwanted material. Furthermore, when the rod (or a mounting plate) is assembled to the rigid sole by gluing, it ensures a continuity of the bonding surface which can only be conducive to holding the assembly.

In all cases, the rigid sole 10 is provided to allow the anchoring of a connecting wedge (not shown) of a binding device of the shoe. For this, the rigid sole is provided with means for anchoring the wedge. According to the invention, and as is particularly apparent from Figure 3, these means comprise an anchoring insert 16 which is interposed between upper layers 20 and lower 22 composite rigid sole, the insert 16 being provided to allow fixing, under the sole 10, the shim.

In the example illustrated in Figures 3 and 5, the insert 16 consists of a metal plate which is perforated and which comprises three threaded drums 18 in which anchor screws can be screwed. It is obvious that at least the lower layer of composite material 22 must be pierced (23) to allow access of the screw threaded drums 18 of the insert 16. In the example of Figures 3 and 5, the upper layer 20 is also pierced. The insert may be made of any material compatible with the functions of the insert.

In the examples illustrated in the figures, the rigid sole 10 has a laminated sandwich structure in that, over at least part of its extent, it comprises a core 24 which is sandwiched between the upper and lower layers 20 of laminated composite material.

In a laminated sandwich structure, the bending of the structure results in a stress on the outer layers (generally thin, in this case the lower and upper layers 22 of composite material) essentially in tension or in compression in their general plane. The inner layer (in this case the core 24), which generally has a thickness much greater than that of the outer layers, is essentially stressed in compression in the direction of its thickness, and in shear in its general plane. In this way, for the inner layer, light materials are generally used, most often cellular materials having a bulk density of less than 400 kg / m 3 and / or woody materials such as wood or other wood-based materials. . These materials are generally substantially rigid in compression in the direction of their thickness, at least in the field of efforts for which the structure is provided. On the other hand, these materials generally have low resistance to bending and pulling. For the outer layers, the composite materials composed of layers of fibers embedded in a plastic resin are appreciated for their high mechanical properties and for their relative ease of use.

In a sandwich structure, the core has a role in maintaining the spacing of the outer layers, which take up most of the efforts in games. The core can be made with very different materials. It can thus be a rigid foam (type PVC, polystyrene, etc ...), a rigid foam reinforced by beads or glass fibers, a woody material (wood or wood-based ), a material honeycomb type (cardboard, aramid, etc ...).

The core can also be made in the form of a material which, without being particularly light, makes it possible, for example by means of particularly easy shaping, to give the sole complex geometric shapes. In this case, we can choose to make the core in a dense material, including a traditional plastic material (polyethylene, polypropylene, polyamide, etc ...), optionally thermoplastic, this core then being advantageously shaped by injection molding. With such materials, which intrinsically have good mechanical strength, it can be expected that the core is hollow.

The anchoring insert 16 is, according to the invention, interposed between the layers of composite material, it also forms a core within the sole.

• être directement juxtaposé au contact du noyau (c.f. Figures 3 et 5);
• être intégré à l'intérieur du noyau (par exemple par surmoulage d'un noyau en matière plastique moulable autour de l'insert, c.f. Figure 6) ;
• être séparé du noyau par une couche de séparation, par exemple par au moins une couche de matériau composite intermédiaire (c.f. Figure 7).

Depending on the type of core used, the insert can for example:

• be directly juxtaposed in contact with the nucleus (see Figures 3 and 5);
• be integrated inside the core (for example by overmoulding a moldable plastic core around the insert, cf Figure 6);
• be separated from the core by a separation layer, for example by at least one layer of intermediate composite material (see Figure 7).

In the case where the insert 16 and the core 24 are juxtaposed, it may be wise that the insert is at least partially received in a housing arranged in a face of the core, in order to obtain a core-insert form regular outer, facilitating the obtaining of an upper surface 11 of smooth sole. This housing can be made by machining or, if the core is molded, obtained directly during its molding.

However, in a particularly advantageous embodiment, the insert is embedded in a face of the core so that it is received in a housing whose shape corresponds exactly to that of the insert.

FIG. 4 illustrates a particularly advantageous embodiment of such an incrustation, in which the insert 16 is force-encrusted in the material of the core 24, by example by placing under the effect of a press, the core material 24 being compressed under the insert.

Thus, FIG. 4 illustrates a core blank 24 made, for example, of a cellular material such as a rigid polyurethane foam reinforced at least locally by glass fibers. Such a material has for example a bulk density of the order of 200 to 500 kg / m3. The blank is made in the form of a pre-cut plate which has a constant thickness (for example about 2 or 3 mm) and a contour corresponding to that of the boss 14 of the underside of the rigid sole 10. In this example of realization, the blank of the core 24 has dimensions, both in length and width, smaller than the full dimensions of the rigid sole 10. This blank has a maximum width of the order of 60 to 85% of the width of the rigid sole 10 in the area corresponding to the metatarsal joint, and a length of about 3/4 of the sole, so that the core stops just in front of the heel, at the back of the arch .

The core blank is for example provided with holes 26 for receiving the threaded drums 18 of the insert 16, so as to achieve a relative positioning of the two elements relative to each other. The two elements are then brought under a press to be compressed vertically between a lower tool 30 and an upper tool 32. Under the effect of the pressing force, the insert is embedded in the blank of the core. printing an impression exactly corresponding to its shape by permanent plastic deformation of the material of the nucleus. In the example illustrated, the insert has a curved longitudinal profile which corresponds to the curved shape of the rigid soleplate 10, which has, at the level of the metatarsophalangeal zone, a longitudinal radius of curvature of the order of 50 to 200 mm . Therefore, it can be chosen that the tools 30, 32 of the press have curved active faces. In this way, it will be possible, during the incrustation operation of the insert, preform the core by giving it a curved shape close to that of the sole. By this incrustation operation, the material of the core which is in correspondence with the insert is compressed and densified, which tends to increase its resistance to any subsequent compression. Optionally, the operation can be performed hot, at a temperature at which the core material is more malleable. The core then undergoes, under the insert, a kind of thermoforming with compression of material. In the illustrated example, the insert is embedded in the upper face of the core, but it could also be expected that it is embedded in the underside of the core. As described, this operation of embedding the insert in the core can be performed before assembly and manufacture of the rigid sole.

This can take place by conforming by superimposing, on the cavity of a lower mold half-mold, layers of fibers intended to form the lower layer 22, then the core-insert assembly, and then layers of fibers. intended to form the upper layer 20, closing the cavity with an upper half-mold, by injecting into the mold a resin and maintaining the whole under a pressure and at a temperature allowing the polymerization of the resin. This operation can also be carried out using pre-impregnated fiber plies, thus not requiring resin injection.

Insofar as the manufacture of the soleplate is carried out in a mold under pressure, it is also possible to provide that the incrustation operation of the insert 16 in the core blank 24, as described with reference to FIG. 4, not made in the form of a separate prior step, but directly during the closure of the mold for manufacturing the sole.

In the embodiment of Figures 3 and 5, we see that the insert 16 with its drums 18, has a thickness which is substantially equal to that of the core blank. In this case, the insert is substantially in contact both with the upper layer 20 and with the lower layer 22 of the composite structure of the sole 10. However, it could also be provided that the thickness of the insert is greater. weak than that of the nucleus, or on the contrary, it is superior. In the latter case, it can then be provided that at least a portion of the insert (for example the lower end of the barrels of the insert) is flush with one of the faces of the sole (the lower face in this case) or protrudes outwards with respect to this face. In the latter case, it will preferably be provided that the bores 23 of the lower layer (and possibly those of the upper layer) corresponding to the passage of the anchoring means are made before the assembly operation, in particular using plies. pre-drilled fibers. The holes can then serve as positioning index of the various elements in the conforming mold. In other cases, the holes 23 may be made after the shaping operation of the sole.

In the variant of Figure 6, the insert is embedded in the core. This can be achieved by overmolding the core around the insert. The core can then be made with any moldable material. In the illustrated case, the thickness of the insert 16 is less than that of the core 24 and the insert is not flush in the upper face or in the lower face of the core. It could of course be expected that it is flush in one or the other of the faces. Note also that here the composite upper layer 20 is not pierced.

In the variant of Figure 7, it is noted that the insert 16 and the core 24 are vertically superimposed but they are separated by an intermediate layer 34. This intermediate layer 34 is for example a composite layer formed of one or more fiber sheets impregnated with resin. The insert 16 is thus directly interposed between the upper layer 20 and the intermediate layer 34, thus being embedded in a particularly strong laminate composite structure. Avoiding direct contact of the insert 16 with the core 24 limits the forces to which the core is likely to be subjected. In this way, the material chosen for the core may be lighter. It could of course be provided that the insert 16 is interposed between the lower layer 22 and the intermediate layer 34.

The examples described show cases where the sole is sandwich type, with an inner core, and where the insert is partially integrated or juxtaposed vertically to the core. However, it could for example be provided that the insert has a thickness substantially equal to that of the core and that it is positioned in a cutout of the core, or on an edge thereof, the the insert material being entirely substituted for that of the core, and the insert then being in contact by its two faces with both the composite bottom layer 22 and the composite top layer 20.

It can also be envisaged that the soleplate does not have a core, the insert being alone interposed between the lower layer 22 and upper 20 of the composite laminate structure. The insert itself forms a core in the sense that it induces a spacing between the stratified upper and lower layers. This case can also be produced with a sandwich structure sole that has a core in one zone and an insert in another zone, both being sandwiched between the composite lower and upper layers.

The invention has just been described in the case where the anchoring means comprise a threaded insert intended to cooperate with screws. However, other embodiments of the anchoring means may be provided. It can thus be provided that the insert comprises threaded rods protruding outwardly below the underside of the sole. It can further be provided that the anchoring means comprise quarter-turn mounting mechanisms rather than threaded means. It can also be provided that the interface between the sole and the wedge is made in the form of a plate external to the sole, but that this plate has extensions in the form of anchoring inserts interposed in the sole, in accordance with the teachings of the invention. The invention may also be implemented for a soleplate having several distinct inserts, having any kind of geometry.

In any case, the invention makes it possible to produce, in a simple and economical manner, a light and very rigid sole, having all the guarantees of strength of the anchoring means of the hold, and further having a minimum thickness, particularly at level of the metatarsophalangeal joint area, this criterion being very important for use of the shoe in competition.

Claims (13)

Sole for a bicycle shoe, of the type in which the sole comprises at least one upper layer (20) and one lower layer (22), each made of composite laminate material comprising at least one layer of fibers impregnated with a resin, characterized in that that the soleplate (10) comprises, interposed between the composite top layer (20) and the composite bottom layer (22), at least one anchoring insert (16) which is provided to allow attachment, under the sole, of a connecting member of the sole (10) to a bicycle pedal. Sole according to claim 1, characterized in that it comprises at least one core (24) which is interposed between the upper layers (20) and lower (22) composite. Sole according to claim 2, characterized in that the insert (16) is directly juxtaposed to the core (24). Sole according to one of claims 2 or 3, characterized in that the insert (16) is received in a corresponding housing formed in a face of the core (24). Sole according to claim 4, characterized in that the insert (16) is embedded in the core (24). Sole according to claim 5, characterized in that the insert (16) is embedded in the core (24) by a pressing operation. Sole according to claim 2, characterized in that the insert (16) is integrated in the core (24). Sole according to claim 7, characterized in that the insert (16) is integrated in the core (24) by overmolding the core around the insert. Sole according to claim 2, characterized in that the insert (16) and the core (24) are superimposed and are separated by an intermediate layer (34). Sole according to any one of claims 2 to 9, characterized in that the core (24) is made of cellular material. Sole according to any one of claims 2 to 9, characterized in that the core (24) is made of a dense material. Sole according to any one of the preceding claims, characterized in that the insert (16) is made of metal. Bicycle sole shoe, characterized in that it comprises a sole (10) made according to any one of the preceding claims.

Images